Синтез і дослідження властивостей плівок органо-неорганічних перовскітів безконтактними методами

• Дата: 2021
• Автори: Kostylyov, V.P., Sachenko, A.V., Vlasiuk, V.M., Sokolovskyi, I.O., Kobylianska, S.D., Torchyniuk, P.V., V’yunov, O.I., Belous, A.G.
• Формат: Стаття
• Мова: English
• Опубліковано: Publishing house "Academperiodika" 2021
• Теми: surface photovoltage; perovskite film; diffusion length; transmission spectra; Urbach effect; Surface physics; Polymers and organic compounds; Photoconduction and photovoltaic effects; поверхнева фотонапруга; плiвка перовскiту; довжина дифузiї; передача спектрiв; ефект Урбаха; Фізика поверхні; Полімери і органічні сполуки; Фотопровідність і фотовольтаїчні ефекти
• Онлайн доступ: https://ujp.bitp.kiev.ua/index.php/ujp/article/view/2020080
• Назва журналу: Ukrainian Journal of Physics

We present the results of studies of the photoelectric properties of perovskite CH3NH3PbI2.98Cl0.02 films deposited on a glass substrate using the spin-coating method. The unit cell parameters of perovskite are determined, by using X-ray diff ractometry. It is shown that the fi lm morphology represents a net of non-oriented needle-like structures with significant roughness and porosity. In order to investigate the properties of the films obtained, we used non-contact methods such as transmission and reflection measurements and the measurements of the spectral characteristics of the small-signal surface photovoltage. The non-contact method of spectral characteristics of the small-signal surface photovoltage and the transmission method reveal information about the external quantum yield in the films studied and about the diffusion length of minority carriers in the perovskite films. As a result of this analysis, it has been established that the films are naturally textured, and their bandgap is 1.59 eV. It is shown that, in order to correctly determine the absorption coefficient and the bandgap values, the Urbach effect should be accounted for. The diffusion length of minority carriers is longer than the fi lm thickness, which is equal to 400 nm. The films obtained are promising materials for solar cells and optoelectronic devices.